Atiq Ferdows, Wuijster Esmee, de Maat Moniek P M, Kruip Marieke J H A, Cnossen Marjon H, Leebeek Frank W G
Department of Hematology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.
Department of Pediatric Hematology, Erasmus MC-Sophia Children's Hospital, University Medical Center Rotterdam, Rotterdam, The Netherlands.
J Thromb Haemost. 2021 Mar;19(3):719-731. doi: 10.1111/jth.15227. Epub 2021 Jan 24.
Important diagnostic and clinical aspects of moderately reduced von Willebrand factor (VWF) levels are still unknown. There is no clear evidence which cutoff value (0.50 vs 0.60 IU/ml) should be used to diagnose "low VWF." Also, the incidence of bleeding after the diagnosis has been made, and risk factors for bleeding are unknown yet.
To investigate the incidence of postsurgical bleeding, postpartum hemorrhage (PPH), and traumatic and spontaneous bleeding after low VWF diagnosis, and to develop a risk score to predict future bleeding.
We performed a cohort study in patients with historically lowest VWF levels of 0.31 to 0.60 IU/ml. Clinical data of patients were retrospectively collected.
We included 439 patients with low VWF. During a follow-up of 6.3 ± 3.7 years, 259 surgical procedures, 81 deliveries, and 109 spontaneous and traumatic bleeding episodes were reported. The incidence of postsurgical bleeding was 2.7%, whereas 10% of deliveries was complicated by PPH. Overall, 65 patients (14.8%) had bleeding requiring treatment, which was not different between patients with historically lowest VWF levels of 0.31-0.50 and 0.51-0.60 IU/ml (p = .154). Age <18 years, abnormal bleeding score at diagnosis, and being referred for bleeding symptoms at the time of diagnosis were independent risk factors for bleeding during follow-up, and therefore included in the risk score.
The cutoff value of low VWF diagnosis should be set at 0.60 IU/ml. Furthermore, a risk score is developed to identify individuals with a high risk for bleeding after low VWF diagnosis.
血管性血友病因子（VWF）水平中度降低的重要诊断和临床方面仍不清楚。尚无明确证据表明应使用哪个临界值（0.50 与 0.60 IU/ml）来诊断“低 VWF”。此外，诊断后出血的发生率以及出血的危险因素尚不清楚。
调查低 VWF 诊断后手术出血、产后出血（PPH）以及创伤性和自发性出血的发生率，并制定一个风险评分来预测未来出血情况。
我们对历史上 VWF 水平最低为 0.31 至 0.60 IU/ml 的患者进行了一项队列研究。回顾性收集患者的临床资料。
我们纳入了 439 例低 VWF 患者。在 6.3±3.7 年的随访期间，报告了 259 例外科手术、81 例分娩以及 109 例自发性和创伤性出血事件。手术出血的发生率为 2.7%，而 10%的分娩并发 PPH。总体而言，65 例患者（14.8%）发生了需要治疗的出血，历史上 VWF 水平最低为 0.31 - 0.50 和 0.51 - 0.60 IU/ml 的患者之间无差异（p = 0.154）。年龄<18 岁、诊断时异常出血评分以及诊断时因出血症状转诊是随访期间出血的独立危险因素，因此纳入风险评分。
低 VWF 诊断的临界值应设定为 0.60 IU/ml。此外，制定了一个风险评分来识别低 VWF 诊断后出血风险高的个体。
